图论/暴力 Codeforces Beta Round #94 (Div. 2 Only) B. Students and Shoelaces

题目传送门

 /*
     图论/暴力：这是个连通的问题，每一次把所有度数为1的砍掉，把连接的点再砍掉，总之很神奇，不懂:)
 */
 #include <cstdio>
 #include <cstring>
 #include <algorithm>
 #include <cmath>
 using namespace std;

 const int MAXN = 1e2 + ;
 const int INF = 0x3f3f3f3f;
 int cnt[MAXN];
 int a[MAXN];
 bool g[MAXN][MAXN];

 int main(void)        //Codeforces Beta Round #94 (Div. 2 Only) B. Students and Shoelaces
 {
 //    freopen ("B.in", "r", stdin);
     int n, m;
     while (scanf ("%d%d", &n, &m) == )
     {
         memset (cnt, , sizeof (cnt));
         memset (g, false, sizeof (g));
         for (int i=; i<=m; ++i)
         {
             int x, y;    scanf ("%d%d", &x, &y);
             cnt[x]++;    cnt[y]++;
             g[x][y] = g[y][x] = true;
         }

         int t = ;    int ans = -;
         do{
             t = ;
             for (int i=; i<=n; ++i)
             {
                 if (cnt[i] == )    {cnt[i]--;    a[++t] = i;}
             }
             for (int i=; i<=t; ++i)
             {
                 for (int j=; j<=n; ++j)
                 {
                     if (g[a[i]][j] == true)    cnt[j]--;
                 }
             }
             ++ans;
         }while (t > );

         printf ("%d\n", ans);
     }

     return ;
 }

 /*
 3 3
 1 2
 2 3
 3 1
 6 3
 1 2
 2 3
 3 4
 6 5
 1 4
 2 4
 3 4
 5 4
 6 4
 */